Updated June 2026 · Last reviewed for accuracy and compliance.
Educational only. Canna Health Amsterdam sells food supplements and cosmetics. Our products are not medicines and are not approved for the prevention, diagnosis, treatment or cure of any disease. THCP is intoxicating at higher doses; this article is a research-focused companion to our practical “what is THCP” pillar, not a recommendation to substitute THCP for any medication.
THCP — tetrahydrocannabiphorol — was reported as a novel phytocannabinoid in December 2019, and the field has not quite been the same since. The cannabinoid had been hiding in plain sight in cannabis for decades, missed by every preceding generation of analytical chemistry, because the alkyl side chain that distinguishes it from THC is two carbon atoms longer than anyone was looking for. When Cinzia Citti and her colleagues at the University of Modena and Reggio Emilia identified it, they did not just add another minor cannabinoid to the list — they redrew part of the cannabinoid pharmacology landscape and forced a reconsideration of what a “naturally occurring” cannabinoid can be.
This guide is the deeper science companion to our practical what is THCP pillar. Where that guide covers what THCP is, how to use it and where it ships, this one covers why THCP is genuinely revolutionary in cannabinoid science: the analytical chemistry advances that made the discovery possible, the phorol cannabinoid family that THCP belongs to, the structure-activity relationship history that predicted compounds like THCP decades before any were found in nature, the parallel discovery of CBDP, where the research has gone since 2019, what cultivar breeders are doing with the finding, and what the next decade of THCP science could look like.
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Why THCP is genuinely revolutionary — three reasons
The word “revolutionary” gets thrown around freely in cannabinoid marketing, usually for compounds that are nothing of the sort. THCP is one of the rare cases where the label is defensible. Three reasons:
First, THCP shifted the frontier of natural cannabinoid potency. Until 2019, the most cannabimimetic naturally occurring phytocannabinoid was Δ9-THC. Synthetic CB1 agonists with higher affinity existed (HU-210, JWH-018, the indazole cannabinoids that turn up in “spice” products), but every one of those was a laboratory creation. THCP is naturally produced — at trace levels, but unambiguously — and has higher CB1 affinity than THC. That changes the conceptual map of what is biologically possible in the cannabis plant.
Second, THCP is part of a broader phorol cannabinoid family that nobody had hunted for systematically. The CBDP that Citti et al. identified alongside THCP — the cannabidiol analogue with a seven-carbon side chain — suggests there is a whole minor-cannabinoid landscape with longer alkyl tails waiting to be mapped. CBC-P, CBG-P, CBN-P are all theoretically possible. The 2019 paper opened a research programme that may continue for a decade.
Third, the discovery is a methodological milestone in analytical chemistry. THCP was found because Citti’s team applied high-resolution mass spectrometry coupled with liquid chromatography to cannabis material at sensitivities earlier groups had not used in this context. The cannabinoid was always there; the tools to see it weren’t. This is a useful reminder that “what is in cannabis” is partly a function of what we currently know how to detect.
The Citti 2019 discovery — methodology in detail
The original paper is the most-cited primary reference for everything written about THCP since (Citti et al. 2019, Scientific Reports). Worth reading the methodology section in detail — it is what made the discovery possible.
Sample material — FM2 medical cannabis
The team worked with FM2, a medical cannabis cultivar produced under contract by the Stabilimento Chimico Farmaceutico Militare in Florence for the Italian medical cannabis programme. FM2 is a standardised medical cannabis variety with a characterised cannabinoid profile, which made it a sensible starting point — the matrix is well understood, contaminants are minimised, and cannabinoid biosynthesis is active.
Analytical approach — UHPLC-HRMS
Ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry, using Q-Exactive Orbitrap instrumentation. This is the workhorse method for trace-level natural product characterisation in the 2020s. The combination of high chromatographic resolution (separating closely related molecules) with accurate mass measurement (identifying the molecular formula from the exact mass) is what enabled the team to detect cannabinoids present at well under 0.01% of the dry biomass mass.
Structure confirmation
Detecting an unknown compound by mass spectrometry tells you its molecular formula but not its full structure. The team isolated THCP and CBDP in sufficient quantity to characterise them by NMR (nuclear magnetic resonance) spectroscopy, which confirmed the seven-carbon (heptyl) side chain structure and ruled out structural alternatives. This combination of chromatography + mass spectrometry + NMR is the gold-standard workflow for novel natural product discovery.
Biological characterisation
Once the structures were confirmed, the team ran radioligand binding assays for CB1 and CB2 receptors and the standard mouse tetrad assays (analgesia by tail flick, hypothermia by rectal probe, hypolocomotion by open field, catalepsy by ring test). The tetrad is a four-test battery widely used to detect cannabinoid receptor agonism in vivo — passing all four is the diagnostic signature of a CB1-active compound. THCP passed at lower doses than THC.
Why THCP wasn’t discovered before 2019
This is one of the most-asked questions about THCP, and the answer is genuinely interesting because it sits at the intersection of analytical chemistry, cultivar selection and unconscious assumption.
Reason one — trace concentrations
THCP is present in cannabis at 0.001-0.0029% by dry mass — at least three orders of magnitude lower than THC content (typically 5-25%). Older HPLC methods optimised for THC quantitation were not sensitive enough to reliably detect compounds at sub-0.01% levels.
Reason two — co-elution with THC
THCP and THC are structurally similar. On many older HPLC columns and gradients, their retention times overlap or are very close. Without the resolving power of modern UHPLC, a small THCP peak would be hidden under the much larger THC peak.
Reason three — researcher expectation
Cannabinoid chemists for decades worked from a mental model in which the natural cannabinoid family had side chains of one to five carbons, capped at the pentyl (five-carbon) side chain in THC. Longer-chain analogues were considered a synthetic-chemistry territory — interesting laboratory targets for structure-activity studies but not natural products. When you do not expect a compound to be there, you may not look for it.
Reason four — Italian medical cultivar
FM2 was selected from medical cannabis programmes optimised for consistent cannabinoid profile. The cultivar may have an unusually high THCP : THC ratio compared to recreational or unselected cannabis. Other cultivars sampled since 2019 have shown variable THCP content, and breeding work has accelerated since the discovery.
Structure-activity relationship — what THCP confirms
The relationship between cannabinoid side chain length and CB1 receptor activity is one of the longest-running structure-activity questions in cannabinoid chemistry. Roger Pertwee and colleagues had laid out the basic framework in synthetic SAR work decades before THCP was found:
• 1-2 carbon side chain — negligible CB1 activity. Methyl- and ethyl-cannabinoids are essentially inert at CB1.
• 3 carbon side chain (propyl) — modest activity. THCV (Δ9-tetrahydrocannabivarin) sits here.
• 5 carbon side chain (pentyl) — THC’s side chain. The reference activity.
• 6 carbon side chain (hexyl) — increased activity in synthetic analogues. No natural hexyl cannabinoid widely reported.
• 7 carbon side chain (heptyl) — substantially higher activity in synthetic analogues. THCP confirmed a heptyl cannabinoid naturally exists.
• 8+ carbon side chain — synthetic compounds with even higher CB1 affinity exist. Pertwee’s work showed activity peaks around 8 carbons before declining.
THCP’s arrival in the natural cannabinoid pantheon validated the synthetic SAR predictions in a way that purely synthetic compounds could not. It also raised the question: if a seven-carbon natural cannabinoid exists, what else does?
The phorol cannabinoid family — what comes next
THCP is not alone. The Citti 2019 paper also identified CBDP — the cannabidiol analogue with the same seven-carbon side chain. By analogy with the standard cannabinoid family (CBD → CBG → CBN → CBC → THC), we should expect:
• CBDP — already identified in the Citti paper. Cannabidiphorol. Non-intoxicating analogue of CBD with the heptyl tail.
• CBGP — cannabigerophorol. The biosynthetic precursor of the phorol family by analogy with CBG. Not yet widely reported in peer-reviewed literature.
• CBNP — cannabinophorol. The oxidation product of THCP, by analogy with CBN forming from THC.
• CBCP — cannabichromenphorol. By analogy with CBC.
• THCVP — three-carbon side chain version of THCP, if the biosynthetic logic carries.
Some of these have been mentioned in subsequent papers and in industry coverage. Others are theoretical structures awaiting characterisation. The next decade of cannabinoid analytical chemistry is likely to map this phorol landscape much more completely.
CBDP — the under-discussed half of the 2019 discovery
CBDP got far less press attention than THCP because CBDP is non-intoxicating and the headline-grabbing finding was THCP’s CB1 affinity. CBDP is arguably the more interesting compound for food-supplement applications precisely because it is non-intoxicating.
What we know about CBDP from the Citti paper and subsequent work is limited. The structural analogy with CBD predicts:
• Likely 5-HT1A activity (CBD is a 5-HT1A partial agonist).
• Likely TRPV1 activity (CBD activates TRPV1).
• Likely PPAR-γ activity.
• Likely indirect ECS modulation rather than CB1 agonism.
Whether CBDP is more potent than CBD at these targets — or whether the side chain length matters less for non-CB1 targets than for CB1 — is an open research question. CBDP food supplements are not yet widely commercially available; the supply chain is still being built.
Where THCP research has gone since 2019
The Citti paper opened several research threads. A non-exhaustive map:
Receptor pharmacology refinement
Follow-up work has examined THCP’s functional behaviour at CB1 — partial agonist versus full agonist, biased signalling, signalling pathway preferences. Pharmacological depth beyond the initial binding affinity number is still being characterised.
Metabolism and pharmacokinetics
What metabolites does THCP produce? How long does it stay in the body? Do THCP metabolites cross-react with standard THC immunoassays (the basis of workplace drug tests)? Early work suggests yes — which is why athletes and drug-tested workers should not use THCP. The detailed pharmacokinetic profile is still being characterised.
Cultivar surveys
Researchers have begun surveying cannabis cultivars for THCP content. Findings have been variable. Some cultivars show essentially no detectable THCP; others show meaningfully more than FM2. This variability points to genetic and biosynthetic factors that breeders are starting to exploit.
Pain and analgesia research
The tetrad assay results in the Citti paper showed THCP produced analgesia-like behaviour in mice at low doses. Subsequent work has continued to examine THCP’s potential in pain pathways, though this remains pre-clinical and is not a basis for therapeutic claims. See THCP and pain research for the published context.
Regulatory categorisation
National regulators have had to decide whether THCP is “THC for legal purposes”, a distinct controlled substance, a permitted novel-food cannabinoid, or unaddressed by existing legislation. Different jurisdictions have arrived at different answers. Greece classified THCP as controlled in 2025 (context). UK and Portugal permit it under food-supplement framing. Germany, the Netherlands and others remain cautious.
Cultivar and breeding implications
Cannabis breeders have started selecting for THCP content. The economics are obvious: a cultivar with measurable THCP at 0.02% rather than 0.002% delivers ten times the THCP per kilogram of biomass, which transforms extraction economics. Two breeding strategies are in play:
Selection from existing genetics. Screening hundreds of cultivars by UHPLC-HRMS, identifying outliers with elevated THCP, then crossing the outliers to concentrate the trait. This is classical phenotype-driven breeding.
Marker-assisted selection. Once the genes responsible for the seven-carbon side chain biosynthesis are identified, breeders can select for the genotype rather than the phenotype, accelerating the work substantially. This is still at the research stage.
The biosynthetic question is interesting in its own right. Does the cannabis plant have a separate enzyme that produces seven-carbon polyketide starters, or is THCP a side product of the same enzyme that produces the standard five-carbon family? The answer affects breeding strategy and extends to the broader phorol cannabinoid landscape.
How the food supplement industry has responded
THCP went from peer-reviewed discovery to commercial food supplement category in roughly two years — fast even by cannabinoid industry standards. The supply chain that emerged:
Production. A small number of specialised extractors produce THCP-rich concentrate from selected biomass. Output is much smaller than CBD or CBG production. Pricing reflects scarcity.
Formulation. Most commercial THCP products dilute the concentrate into either MCT carrier oil (sublingual tinctures) or gummy bases (edibles). The carrier matters less for THCP than for CBD because the doses are smaller and the effect per milligram is larger.
Quality control. Per-batch Certificates of Analysis are essential. The unregulated long tail of the cannabinoid market includes products with cannabinoid contents wildly different from label claims — particularly problematic with a high-potency compound like THCP where a 5x mislabel can be the difference between a tolerable session and a hospital visit. Our quality framework: CAN certification.
Catalogue placement. Where THCP fits in our range. THCP Tutti Frutti Gummies ship to most EU markets where shipping is permitted; THCP Oil 600mg to the UK and Portugal only. For that market’s context see our UK THC gummies guide. See the what is THCP pillar for the full shipping policy.
Common THCP misconceptions
“THCP is synthetic”
No. THCP is a naturally occurring phytocannabinoid produced in trace amounts by cannabis. This distinguishes it from semi-synthetic cannabinoids like HHC or HHC-P (which are produced by chemical conversion of CBD) and from fully synthetic cannabinoids like the JWH series (which are made in laboratories with no plant intermediate).
“THCP is 33 times stronger than THC”
THCP has approximately 33 times higher CB1 binding affinity than THC in radioligand assays. Binding affinity is not the same thing as subjective potency at typical product doses. Practical product effects depend on the dose, route, individual metabolism and personal response. Treat THCP as a strong cannabinoid that requires careful dose titration — not as “THC times 33”.
“THCP was created in a lab”
No. THCP was identified in plant material. The fact that the analytical chemistry needed to find it was sophisticated is sometimes confused with the cannabinoid itself being artificial. The Citti team isolated, characterised and tested a compound the plant biosynthesises naturally.
“THCP is the same as HHC-P”
No. HHC-P is a semi-synthetic compound produced by hydrogenation of THCP or related precursors. THCP is the natural starting compound. The two have related structures but different origins, different regulatory categorisations and different supply chains. We have exited HHC-P; THCP remains in catalogue.
“If THCP is more natural, it must be safer”
“Natural” is not a safety claim. THCP’s higher CB1 affinity means dose precision matters more, not less, than with THC. Edible overshoots are the most common source of bad experiences with high-affinity cannabinoid products. Start low, wait the full onset window, do not chase the effect.
Where THCP science could go next — the 2030 outlook
Predicting research trajectories is risky, but a few directions are plausible:
Complete phorol family characterisation. CBDP, CBNP, CBGP, CBCP and their acid forms — peer-reviewed structural and pharmacological characterisation, with reference standards available to other labs.
Functional pharmacology depth. Beyond receptor binding, the biased signalling profile of THCP at CB1 — which downstream pathways it preferentially activates — could matter for understanding why some users find THCP’s subjective character distinct from THC’s.
Cultivar genetics. Identification of the biosynthetic enzymes responsible for the heptyl side chain. Marker-assisted breeding for cultivars with commercially meaningful THCP content.
Regulatory clarity. EU-level guidance on THCP classification. Either harmonised novel-food acceptance or a clear controlled-substance categorisation. The current patchwork is bad for consumers and producers alike.
Clinical research. If THCP’s pharmacology becomes well-enough characterised to interest pharmaceutical developers, formal clinical trials in pain or other indications are plausible. None of this would be relevant to food-supplement THCP, which would remain a wellness-category product.
Frequently asked questions — THCP science
Who discovered THCP?
Cinzia Citti, Maria Angela Vandelli, Giuseppe Cannazza and colleagues at the University of Modena and Reggio Emilia, with collaborators. The paper was published in Scientific Reports in December 2019.
Why wasn’t THCP discovered earlier?
Trace concentrations (around 0.001-0.0029% in the original sample), co-elution with much larger THC peaks on older HPLC methods, researcher expectation that the natural cannabinoid family stopped at five-carbon side chains, and the specific medical cultivar (FM2) sampled may have a higher-than-average THCP content.
Is THCP a natural cannabinoid?
Yes — produced by the cannabis plant in trace amounts. Not a semi-synthetic.
What is the structural difference between THCP and THC?
A seven-carbon (heptyl) alkyl side chain instead of THC’s five-carbon (pentyl) side chain. Two extra CH₂ units.
What is CBDP?
Cannabidiphorol — the non-intoxicating CBD analogue with the same seven-carbon side chain, identified by Citti et al. alongside THCP.
How does THCP’s CB1 affinity compare to THC?
Approximately 33 times higher in radioligand binding assays (Ki ~1.2 nM vs THC’s ~40 nM). Binding affinity is one input into subjective potency, not the whole story.
Is THCP stronger than THC in practical use?
At dose-adjusted product use, yes — a smaller mass of THCP produces effects comparable to a larger mass of THC. Treat it as a strong cannabinoid requiring careful titration.
Where can I read the original Citti paper?
Are there other phorol cannabinoids?
CBDP has been identified. CBGP, CBNP, CBCP and others are theoretical structures awaiting characterisation. The phorol family is an active research area.
Is THCP being studied medically?
Pre-clinical pharmacology continues. Formal clinical trials are not yet established. Food-supplement THCP is not a medicine and is not approved for any therapeutic indication.
Will more new cannabinoids be discovered?
Yes, almost certainly. The improvement in analytical chemistry that found THCP will find others. The phorol family, the propyl family beyond THCV/CBDV, and other modifications are all under-explored.
Are THCP gummies and oil the same as semi-synthetic HHC products?
No. THCP is a natural cannabinoid extracted from plant material. HHC and HHC-P are semi-synthetic compounds made by chemical conversion. Different origins, different regulatory categorisations.
Does THCP affect drug tests?
Yes — THCP’s metabolites can plausibly cross-react with standard THC immunoassays. Athletes and drug-tested workers should not use THCP.
What countries can I buy THCP in?
Country shipping detail in our what is THCP pillar. UK and Portugal for THCP oil; most EU markets except DE/NL/GR for THCP gummies.
Is THCP legal in the UK?
Yes, sold as a food supplement under the FSA Novel Food framework.
Where to read next
Practical follow-on reading: What Is THCP (practical pillar) · THCP and Pain Research · CBN vs CBG · What Is CBD Oil · What Is CBG Oil · CB2 Receptor Research · CBD Side Effects (drug-interaction framework applies) · CAN Certification · UK THC gummies guide.
THCP food supplements are sold subject to country-specific shipping rules. THCP oil ships only to the UK and Portugal. THCP gummies have wider EU availability but are not shipped to Germany, the Netherlands or Greece. Always confirm the legal position in your jurisdiction before ordering. Information current to June 2026.
